Lubricating system fob rotary engines



T. F. BRACKETT;

LUBRICATING SYSTEM FOR ROTARY ENGINES.

APPLICATION FILED MAY 18. I918.

m \miym g E]. we 0mm {7M 0; .m h r w i E dw I 1 m y m W Q TM WWNW. m

W a 8g RF. BRACKETT.

LUBRICATING svsram ma ROTARY memes. Y

Patented Sept. 23,1919.

4 SHEETS-SHEET 3.

APPLICATION FILED MAY I8. 1918.

T. F. BRACKETT.

LUBRICATING SYSTEM FOR ROTARY ENGINE-S.

. APPLICATION FILED MAY 18. 1918. 1,316,679.

Patented Sept. 23, 1919.

4 SHEETS-SHEET 4.

M Mr TRACY F. BRACKET'T, OF CHICAGO, ILLINOIS.

LUBRICATING SYSTEM FOR ROTARY ENGINES.

Specification of Letters Patent.

Patented Sept. 23, 1919.

Original application filed February 20, 1918, Serial No. 218,345. Divided and this application filed May 18, 1918. Serial No. 235,402.

plurality of cylinders are arranged to move bodily about a common axis which is parallel to the axes of the cylinders, the piston rods of said cylinders being connected to an angle plate which rotates about an axis disposed at an angle to the axis about which the cylinders rotate.

My present invention relates to certain features of the engine disclosed in my Patents Nos. 1,282,179 and 1,282,180, both of which issued October 22, 1918, this application being a division of theapplication (Serial No. 218,345, filed Feb. 20, 1918,)

which resulted in my first mentioned patent.

The objects of this invention are:

First, to provide an engineof the type referred to, which operates in a new and more eflicient manner than engines of the same type which have been heretofore constructed;

Second, to provide an engine o'f-this type with a new and improved system for lubrication.

Other objects, adaptabilities, capabilities, and modifications will appear as". the description proceeds, reference being had to the accompanying drawings, in which Figure 1 is a central longitudinal section through my improved engine, showing certain of the parts in side elevation;

- Fig. 2 is an enlarged sectional detail view taken on the same lineas Fig. 1, but showing certain details of the structure in section which are shown in side elevation in Fig. 1;

Fig. 3 is a transverse section taken on the line 33 of Fig. 1;

Fig. 4 is an enlarged sectional detail taken on line 4-4 of Fig. 3; r

Fig. 5 is a plan view of my improved pistonshowing the details of the connection between the piston and the angle plates;

Fig. 6 is a transverse section on line66 of Fig. 5; i e

Fig. 7 is a longitudinal section on line 7-7 of Fig. 8; and

Fig. 8 is a transverse section on line 88.

of Figs. 5 and 7.

In the drawings the sections are taken looking in the direction of the small arrows and similar characters of reference refer to similar parts throughout the several views.

Referring to the drawings, and for the present in particular to Figs. 1 and 2, the reference character 20 designates the stationary shaft of my improved engine, the outer end of which is keyed to the member 21, the flange 22 of which is prevented from rotating by the flange23 of the I beam support member '24:. The shaft 20 is provided with a pair of spaced bearing portions 25 and 26 respectively, and an intermediate angularly disposed bearing portion 27. The bearing portions 25 and 26 are alined with each other and rotatably support the cylinder carriers 28 and 29 which form the sides of what for convenience will be termed the crank case. The cylinder carrier 28 is provided at its outer periphery with a flange 30 which extends'to and is bolted to the periphcry of the carrier 29 by screws 31. Suitable tapered roller bearings 32 are interposed between the bearing portions 25 and 26 of the shaft 20 and the cylinder carriers.

In that form of my engine which I have illustrated (in Figs. 1 to 8 inclusive) 1 em ploy fourteen cylinders, seven of which are securedv to each of the cylinder carriers by having their craink ends secured in suitable eqiially spaced apertures 33 in the cylinder carriers. As shown in Figs. 1 and 2, the crank ends of these cylinders open into the crank case, thereby facilitating the lubrication of the cylinders, as will be described later on in referring to my improved lubricating system.

Rot-atably mounted upon the angularly disposed portion of the shaft 27 is the angle plate 3 1, which has extending from the periphery thereof at equal angular distances the crank pins 3 5, which are reinforced by a co-aXial pin 36 of chrome nickel steel, the angle plate itself, for the purpose of conso J prises,

pin 53, which has its ends secured in the side.

venience in manufacture, being formed from cast steel. The outer ends of the crank pins are provided with spherical bearings 37, which are rotatably mounted upon the ends of the pins 35. Roller bearings 38 are interposed between the angular bearing 27 and the hub 39 of the angle plate and the hub 40 of a bevel gear4l, which is secured to the angle plate by means of the screws 42. This construction gives the angle plate a two point bearing upon the angularly disposed bearing 27.

The piston heads 43 are lidably mounted in the cylinders 44 and connected by a cylindrical member 45 which forms an extension ofthe'side walls of the pistons, and

' thereby connects the two piston heads so as v to' form in reality a double ended piston.

' means of socket connections formed by the The crank ends of the iston rods 46 are connected with the spherical bearings 37 by inner and outer socket bearing members 47 and .48. These members are secured in the boxlike. housings 49 on'the crank ends of the pistons by means of bolts 50. The hous-.

' ing-49'is provided with a flange 51 for holding the outer socket in position.

The head ends of the-piston rods 46 are connectedwith one of the piston heads 43 by means of a-universal joint 52, which comas shown in 5 to 8 inclusive, the

I walls of the cylinder head and is surround- 4 i if The opposite sides of the bearing 58 are ed by a bushing 54, upon whiohis rotatably mounted the member 55, having the oppositely extended trunnions 56. The outer trunnion 56 is provided with a fiang'e 57,

which prevents the bearing 58 of the piston rod surrounding the member 54 from being displaced outwardly under centrifugal force.

provided with openings '59 through which thebushing 54 extends, the' openings 54 bei ing of sufiicie nt size to permit the necessary relative movement between the bearing 58 and the bushing 54.

From the above description it will be seen that by using a single piston rod and connecting the twm piston heads I am enabled to do away with one piston rod and correspondinglyto simplifv the connections be tween the piston rods and'the crank pins of the angle plate. From an inspection "of Fig. 5 it will be seen that each double ended piston is provided with a central enlargement 60, which Is to permit the crank end of thepiston rods to move laterally as they must do during the operation of the engine.

To one side of these enlargements 60 I secure guide blocks 61, which slide in guides 62 extending between the cylinder carriers. The function of the guide blocks 61 and the guides 62 is to prevent the double ended pistons from rotating about the axes of the cyl inders. The inner socket member 47 is provided with a tapered portion 63 which permits the necessary relative movement between the crank' pins and the piston rods.

In operation the successive power impulses created in the cylinders will be transmitted to the angle plate through the pistons and piston rods, and thereby tend to cause the angle plate to rotate about its axis. In order, however, that each piston may exert its force upon the angle plate during its complete stroke, it is necessary to provide some means to move the cylinders and their contained pistons in substantial unison or synchronismwith the angle plate. I accomplish this by securing a bevel gear 41, previously referred to, to the angle plate 34. This gear meshes with a corresponding bevel gear 64,

which, is mounted upon the boss 65, which extends inwardly from the cylinder carrier 28, there being a screwthreaded connection between the boss 65 and the gear 64. It will of course be apparent that the gear 64 could be secured to the cylinder carrier 28 in any other suitable manner. By the means just described, when the angle plate rotates uncarriers will be rotated therewith, thereby maintaining each cylinder in the proper relation with the corresponding crank pm of the angle plate to permit the piston to exert its force upon the crank pin during the entire stroke of the piston. Due tov the fact that the path described by the spherical bearings 37 when projected upon a plane passing through the cylinders or pistons at right angles to the axes of the cylinders is and socket connection between the piston rods and the angle plate and the universal. joint connection between the piston rods and the piston heads.

vder the influence of the pistons, the cylinder Before proceeding to the description of the mechanism for operating the valves, the structure of the stationary shaft 20 will be described somewhat morein detail. From an inspection of Fig. 2 it will be seen that the bearing portion 25 of the stationary shaft 30 is provided with an angular extension 66, which has a tapered bore for receiv ing the tapered end 67 of the angularly disposed portion 27 of the shaft 20. Suitable keys 68'prevent the rotation of the bearing portion 25 relative to the bearing portion 27. This two piece construction of the shaft 20 is merely for the purpose of convenience in assembling, as it permits the angle plate anal its roller races to be slipped on over the en In my above entitled application I have described my engine as being'provided with exhaust valves 69 and intake valves 70, and have described in detail the mechanism for operating these valves. Inasmuch as the details of the valve operating mechanism do not constitute a part of my present invention, only'those features of the valve actuating mechanism which are conneoted with '10 my improved lubricating system will be described.

Referring to Figs. 1 and 2 the reference character 72 indicates a cylindrical housing which contains bearings for the push rods 73 and 74, which actuate the levers 75 and' tatably mounted therein by means of ball bearings 82. The cam plate 79 is provided with two concentric series of cams 83 and 84 respectively. The outer series of cams 83 actuate the push rods 7 4 and the inner series of cams operate the push rods 73. The cams 83 and 84 are. displaced from each other angularly in such a manner that theintake valves will be operated immediately after the exhaust valves are closed. As described in my application above referred to, I have provided means comprising the compensating plate 85, the spur gear 86 and the external gear 87 for driving the cam plate at the proper speed relative to the engine shaft 40 for opening the intake and exhaust valves in the proper sequence and the proper number of times for each revolution of the engine. It is believed unnecessaryto describe this mechanism in detail, as. it forms no part of my present invention, with the exception of the features which will be referred to later on, which connect it with my improved lubricating system.

For many reasons it is desirable to .pro-

vide engines of this type with meansfor inas suring a 'forced lubrication of all the bearing surfaces. While engines of this type ha e heretofore been provided with means i for securing amore orless forced lubrication of part of their; bearin this means has been more or les's comp icated for the reason that the pumps for producing the forced lubrication are stationarily mounted with respect to the engine. With-such an ar rangement it is a diiiicult matter to maintain 7 the sliding connections in such a condition as to prevent leakage, and'there is also more or less rapid wear of these parts. Further more. in allof prior lubricating systems with whichI am acquainted, the oil has been re to permit the oil to gain access to the bear 7 turned to a stationaryoiltank from which the oil is pumped by the pump and returned to the engine. On account of the fact that this tank is stationary it is also necessary to provide means for returning the oil to this tank, which include sliding connections that. are subject to the same criticism as the connections between the pump, and in order to overcome these difficulties, I mount both the I pump and the oil tank upon my engine in such a manner that they rotate .with the moving parts of the engine.

I will now describe my improved lubricat ing s stem. Situated inside of the flange 30, whic forms the outer side of the crank case is an annular sheet metal partition 88, one edge of which is secured in a recess 89 in the cylinder carrier 28 and rendered oil ti ht by a suitable packing 90. The other e ge of the partition member 88 is provided with a flange 91 which is secured between the outer I periphery of the cylinder carrier 29 and the adjacent end of the. flange 30. The flange 30 and the partition member 88 therefore form i an annular oil tank which surrounds. the 9.0

angle plate 34. Secured .to the side of the cylinder carrier: 28, adjacent the eriphery thereof, is a gear pump 92, detalls of the a construction of which it is believed unnecessary to describe for the reason that they 3 form no part of my present invention. The

intake side of this pump is connected by means of a duct 93 formed in the'cylinder carrier 28 with the oil tank formed bythe' flange 30 and the partition 88. The dis.-

charge side ofthe'pump is connected by'a" v conduit94 with a manifold pipe 95, which? extends longitudinally of the engine, one portion thereof passing through the crank case. One branch 96 of thismanifold is connected with a duct 97 formed in-a power shaft 81, which communicates with a duct 98 formed in the bearing portion 25 of the I stationary shaft through a duct 99 formed in. the boss 80 of the cam late. "Itwill be noted from inspection 0 Fig. 2 that-the end of the boss 80 is spaced slightly from the adjacent end of the power shaft 81 in order I ings 82. In operation the cylindrical hous ing 72 is substantially filled with oil, thereby insuring the proper lubrication of all the moving parts within thi'shousing and caus-Q ing the excess .oil to lie-forced through the ducts 98 and 99. The. housing'72 is provided with a hollow offset portion 100 for' receiving a gear for operating the oil pump, as will be described later on. This housing 100 is in communication with the interior of the housing 72 and is therefore also pro vided with a supply of oil. A second branch 101 of the manifold discharges into an annular recess 102 formed in the inner end of the rotary shaft 81 for the purpose of lubricating the push rods 73 and 74. This oil 13o gradually works its way along the push rods, and in order to prevent the excess of this oil from being forced past the packings 108 surrounding the push rods, 1 provide radially extending ducts 104, which discharge into an annular duct 105 formed on the interior of the housing 72. This duct communicates with the offset portion 100 through the pipe 106. The oil from the housing 7 2 gradually works its way through the roller bearings 32 into the screwthreaded boss 65, from which it is discharged by centrifugal force through an opening 107 formed in one side thereof.

Part of this oil will also find it Way to the gears 41 and 64: and be discharged into the interior of the angle plate 34, which it will be noted is provided with an inwardly extending flange 108, which with the web of the angle plate forms an oil retaining channel for supplying the oil to the ducts 109 formed in the pins 36. The oil is caused to flow outwardly through these ducts under the influence of centrifugal force and finds its way between the pins 85 and the bores in the balls 37. The portion of the oil which overflows the edge of the bores in the balls 37 is forced outwardly by centrifugal force to lubricate the outer surface of the balls 37 and the inner surface of the bearing members 17 and 18. Another portion of this oil overflows into the channel formed by the inwardly extending flanges 110 of the piston rods, which as shown in Fig. 6 are I shaped in cross section. The oil flows along the channels in the piston rods and through an aperture 111 to lubricate the hearing at the crank end of the iston rod, being forced outwardly from this point under the action of centrifugal force.

The duct 98 in the bearing portion 25 discharges into a duct 112 formed in the angularly disposed bearing portion 27 and through a radially extending duct 113 into the hollow boss 39 of the angle plate. From here the oil works through the roller bearing 38 and is cast off by centrifugal force. A part of the oil drained from the bearing 38 will be caught in the open upper end of the trunnion block 55 upon the completion of each instroke and will be forced out through the apertures 114 to lubricate the outer bearing surface of the bushing 54. The portion of the oil which works its way along the bushing 54 will find its way through the apertures 115 and lubricate the bearing surface of the pin I also provide the stationary shaft 20 with a duct 116 which extends from the interior of the crank case to the interior of the housing 11?. This duct is supplied with oil by means of a cup 118 which catches the oil splashed from the adjacent surfaces. The duct 116 supplies the oil to the moving parts in the housing 117'in much the same manner as the duct 97 supplies oil to the housing 72. The manifold 95 is provided with a third branch 119, which supplies oil to an annular chamber in the housing 117 corresponding to the annular chamber 102 in the housing 72. The pipe 120 drains the oil from a channel corresponding to the channel 105 of the housing 72 into the crank case.

From the above description it will be seen that the oil supplied to the bearings is finally discharged into the space formed by the annular partition 88. This partition is substantially flush with the adjacent. surface of the bores of the cylinders, and the 'oil will consequently be forced into the cylinders under centrifugal action to lubricate the cylinder bores and the pistons.

Since a considerable amount of the oil is used in the lubrication of the various parts, when the engine stops running, unless means are provided to prevent it, practically all of this oil would accumulate at the bottom side of the crank case and would gradually work its way past the piston rings into the space between the pistons and the cylinder heads. If it was then attempted to start the engine, the cylinder heads would be forced off. This result could of course be prevented by omitting the partition 88 and making the crank case larger in diameter, so that all of the oil. could accumulate at the bottom of the crank case without reaching a depth suflicient to cause it to flow into the cylinder bores. As above stated, however, it is desirable to make the diameter of the engine as small as possible and this means for preventing the oil from flowing into the cylinders is therefore undesirable, and it is undesirable for the further reason that proper lubrication of the cylinder bores and the pistons could not be maintained.

In order to keep the diameter of the engine as small as possible, I provide the partition member 88 which with the flange 80 forms anannular chamber for the reception of theaoil drained into the crank case from the various bearings. The oil thus drained under the action of centrifugal force flows through'the ducts 121 (see Figs. 3 and 1) which are formed in bosses 122 placed at any desired intervals about the periphery of the cylinder carrier 28 into the annular space formed between the flange 30 and the partition 88. As a result of this structure during the operation of the engine, there is never a considerable amount of oil in the space formed by the annular partition 88, most of the oil being confined in the-space between this partition and the flange 30. \Vhen the engine stops running this oil would tend to flow backwardly through the ducts 121 in the event that any one of these ducts should be located at the bottom of the crank case, and would thereby cause the cylinders to be flooded with oil. In order to prevent this I provide a check valve 123 which is urged against a seat 124 in the duct 121 by a spring 124, the tension of this spring being such that the check valves will remain open as long as the engine is running, but will close at substantially the same time that the engine stops turning over, and will. thereby prevent the backward flow of the oil through the ducts 121.

The means for operating the pump 92 comprises a spur gear 125, which is secured to the inner end of the shaft by a screW-' extending shaft 131. The shaft 131 rotates in a tubular bearing 132 extending from the hollow member 100 and the casing of the gear pump 92. ,The opposite end of the shaft 131 is connected in a well known manner with the gears of the pump 92. As the cylinder carrier 28 revolves about the axis of a shaft 20, the spur gear 126 rolls upon the spur gear 125, and its motion, is transmitted through the shaft127, bevel gears 129 and 130, and the shaft 131 to the pump.

WVhile I have described the details of the preferred embodiment of my invention in connection with the preferred type of engine, it is to be understood that my invention is capable of other adaptabilities and modifications within the scope of the appended claims. 7 Having thus I claim is:

1. The combination with a stationary shaft having an angular bearing portion, of a plurality of cylinders mounted to rotate about the axis of said shaft, with theiraxes parallel thereto, pistons in said cylinders, an angle plate rotatably mounted on said bearing portion, connections between said pistons and said angle plate, means for causing said cylinders to rotate in synchronism with said angle plate, an annular oil tank surrounding said angle plate and secured to said cyline ders, a pump having its intake connected with said tank, a central distributing duct, means for conducting oil from the discharge side of said pump to said distributing duct, means for conducting the oil under cent-rifugal force from said duct to said oil tank, comprising a duct having a non-return valve therein, and driving connections between said stationary shaft and said pump.

2. The combination with a stationary shaft having an angular bearing portion, of a plurality of cylinders mountedv to rotate about the axis of said shaft, with their described my invention, what axes parallel thereto, pistons in said cylinders, an angle plate rotatably mounted on.

said bearing portion, connections between said pistons and said angle plate, means for causing said cylinders to rotate in synchronism with sand angle plate, an annular oil tank surrounding said angle' plate and secured to said cylinders, a: pump having its intake connected with said tank, a central distributing duct, means for conducting oil from the discharge side of said piiinp to said distributing duct, and means for" conducting the oil under centrifugal force from said duct to said oil tank, comprisinga duct havlng a non-return valve therein.

3. The combination with a stationary shaft having an angular bearing portion, of a plurality of cylinders mounted to rotate about the axis of said shaft, with their axes parallel thereto, pistons in said cylinders, an. angle plate rotatably mounted on said bearing portion, connections between said pistons and said angle plate, means for causing said cylinders to rotate in synchronism with said angle plate, an annular oil tank surrounding said'angle plate and secured to said cylinders.

4. In anengine, the combination with a shaft of a pl'ui'ality of cylinders mounted to rotate about the axis of said shaft, with their axes parallel "thereto, an angle'platc rotatably mounted on 'an axis extending at an angle to the axis of said shaft, pistons in said cylinders, connections between said pistons and said angle plate, an annular oil tank secured to said cylinders and, extending around said angle plate, a pump secured to said cylinders, having its intake in communication with said tank, means for returning the oil under the influence of centrifugal force to said oil tank, means for preventing the escape of oil from said tank when the engine is not running, and driving connections between said pump and shaft.

5. In an engine, the combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, an

angle plate rotatably mounted on an axis extending at an angle to the axis of said shaft, pistons in said cylinders, an annular oil tank extending around said angle plate, a pump secured to said cylinders, having its intake in'communication with said tank, means for returning the oil under the influence of centrifugal force to said oil tank. and means for preventing the escape of oil from said tank when the engine is 'not running.

6. An engine comprising a shaft in combination with a plurality of cylinders mounted to rotate about the axis thereof. an angle plate mounted to rotate on an axis disposed at an angle to the axis of said shaft, pistons in said cylinders, driving connections be i so tween said pistons and said angle plate, an

" bination with a plurality of cylinders mount- .j. ed to rotate about the axis thereof, pistons in said cylinders, driving connections between said pistons and said shaft, an annular tank surrounding said driving connections and secured to said cylinders, a pump mounted to rotate'with saidcylinders and said tank, means for conducting oil from having its intake in communication with the discharge side of said pump tothe central portions of said engine, means for re-,

forkpreventing the' oil from-reversing. its

-- direction offflow "when the engine stops. I

- 9, The-combination with-a rotary engine I having a plurality of bearings, of an oil tank r and a-pump mounted on. a rotary portion of said engine, the intake'of saidpump being turning the oil under the mfiuence of centrifugal force to' said tank, and means for preventing back flow of oil when the engine 8.: The combinationwith a rotary engine having a pluralityv of bearings, of an oil tank and a pump mounted on a rotaryportion of said engine, the intake of said. pump being connected with said tank, means for conducting oil 3 from the tank to said bearings, 1

means for returning oil from said bearings to said tank by centrlfugal force, and means -coi1nected with said tank, means for con ducting oil from the tank to said bearings,

and means for returning oil from said bearings to said tank by centrifugal force. 10. The combination with a rotary engine comprising a bearing, of an oil tank and pump mounted on a rotary; portion of said engine, and'means for conducting oil from the discharge side of said pump to said bearing, and from said bearing to said tank.

11. The combinationiwith a rotary engine,

comprising a bearing, of an oil tank mounted on a rotary portion of said engine, a pump, means for connecting the intake of said pump with said tank, means for conducting oil from the discharge side of said pump to said bearing, means for conducting the oil from said'bearing to said tank, and means for preventing reverse flow through said lastnamed means when the engine stops, said last named means being controlled by centrifugal .force.

12. The combination with a rotary engine, comprlsmg a 'bearlng', of an oil tank mounted on a rotary portion of said engine, a

pump, means for connecting theintake of said pump with said tank, means for conducting oil from the discharge side of said pump to said bearing, means for cOnducting the oil from said bearing to said tank, and means for preventing reverse flow through said last named means when the engine stops.

13. The combination with a rotary engine, comprising a bearing, of an oil tank mounted on a rotary portion of said engine, a

pump, means for conducting oil from the discharge side of said pump to said bearing, means for connecting the intake of said ducting the oil from said bearing to said tanlc.

14:. A rotary engine having a closed lubrieating system comprising a pump and a supply oil tank, both of which are secured to a rotary portion of said engine.

15. A rotary engine comprising a shaft,- a crank case rotatably mounted on said shaft,

cylinders mounted on said crank case parallel to the axis of said shaft and opening into said crankcase, the said cylinders extending from one side of the crank case adjacent its periphery, a bearing, means for supplying oil ,to said bearing, means for conducting oil from said bearing to said crank case, and means for preventing the oil from flooding said cylinders when the engine stops.

In witness whereof, I. hereunto subscribe my name this 14th day of May, 1918.

. TRACY F. BRAGKETT.

1 'VVitnesseS:

R. C. MOORE, EARL F. PIERCE. I

so" pump'with said tank, and means for con- 7 

